From APMonitor Documentation

MV_DCOST_SLOPE implements a linear increase in movement penalty (DCOST). The increase in DCOST favors near term movement in the manipulated variable. One issue with a deadband trajectory is a phenomena called controller procrastination where the optimal solution delays a move because it gives an equal objective function to wait one or more cycles. This causes the controller to be stuck in a state of inaction. Favoring movement on the first step of the controller avoids this delay in implementing the needed changes.

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